Metal-bending machine.



H. H. EATON.

- METAL BENDING MACHINE.

APPLlCAT'lON FILED DEC-1, 1910.

Patented Feb. 1, 1916.

2 SHEETS-SHEET I H. H. EATON.

METAL BENDINGMACHINE.

APPLICATION FILED 050.1, 1910.

pnrrnn .sra'rns Parana ornron.

HARRISON H. EATON, OF BEVERLY, MASSACHUSETTS, ASISIGNOR T0 UNITED SI-IOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

METAL-BENDING MACHINE.

Specification of Letters Patent.

Patented Feb. 1, ieie.

Application filed December 1, 1910. Serial No. 595,044.

To all whom it may concern:

Be it known that I, HARRISON H. EATON, a citizen of the United States, residing at Beverly, in the county of Essex and State of Massachusetts, have invented certain Improvements in Metal-Bending Machines, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to metal bending machines and more particularly to machines in which strips or bars of metal maybe bent by power accurately to a predetermined contour.

An object of the invention is to provide a machine in which the stock used in manufacturing cutting dies, and heretofore shaped by hand or by hand operated tools, may be bent by power.

The strip steel from which cutting dies are made has been bent heretofore between two cooperating bending or forming dies, one of which is stationary and the other mounted for reciprocation toward and from the stationary die by manually operated means such as a hand lever. In using an apparatus of this kind considerable strength on the part'of the workman is required to bend the stock, particularly in making lining dies which frequently require strip steel over three inches in width. The work is also fatiguing and consequently both the quantity and the quality of the product is likely to suffer during the latter part of a days work. In order to relieve the workman of this arduous work and also to expedite the operation of shaping the die stock and to improve the accuracy of this operation the present invention contemplates the provision of a machine having cooperating bending or forming dies, and power operated means for reciprocating one of said dies toward and from the other die. In using a machine of this type the workman may devote hisv entire attention to properly placing the stock with respect to the bending dies, this being 7 effected between successive reciprccations of 'In the machine herein illustrated, the Inov able die is 'reciprocated by an eccentric, or the like, formed in a shaft carrying a relatively heavy fly wheel and suitable clutch mechanism may be interposed between said eccentric and fly wheel whereby the momentum of the latter may be imparted to the movable die when the machine is operating but the fly wheel may be disconnected and the movable parts readily brought to rest when it is desired to stop themachine.

In shaping a strip of metal accurately to pattern, it is advantageous to performthe bending operation gradually and progressively, comparing the bent strip with the pattern from time to time as the operation proceeds. The bending or curving of the stock may be progressively increased by causing the two forming dies to approach each other closer and closer at each reciprocation or after each few reciprocations. An important feature of the invention, accordingly, consists in means for varying and regulating the point of nearest approach of the two forming dies. In the machine herein illustrated this is effected by interposing an expansible connection, such as a right and left screw, between the movable forming die and its actuating mechanism and providing means under the control of the operator for expanding or contracting said connection.

Another feature of the invention consists, broadly, in means for determining automatically when the relative adjustment of the two dies may occur. Where, as in the illustrated machine, ascrew is used for varying the relative positions of the cooperating dies it has been found that pressure on the dies in the direction ofthe axis of the screwhas a tendency to cause the screw to rotate and permit separation of the dles. WVith a view to obviating this difficulty a feature of the present inventlon conslsts 1n means acting automatically during the working stroke of the reciprocatory die for preventing such reverse turning of the screw. In this construction the screw may be turned in either direction to vary the point of nearest approach of the die during the reverse stroke of the reciprocatory die.

A further feature'of invention relates to a controlling device for preventing the two forming dies from being moved into such close proximitythat the pressure developed between them, will exceed the limit of safety for the machine. To this end a controlling arm is mounted for movement with the hand wheel above mentioned and adjustable stops are provided in the path of said controlling arm whereby turning of the hand wheel may be limited in accordance with the character of the work being operated upon.

Still another feature of the invention consists in a male die supported at one end by a hinged bar and being free of obstruction at its rear side. Such construction is advantageous in that it permits the movement of bent stock about the rear of the die and so facilitates the use of the machine in the production of dies of small interior dimensions.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which,-

Figure 1 is a view in perspective of a machine embodying the invention. Fig. 2 is a partial view in longitudinal section of the machine shown in Fig. 1. Fig. 3 is a partial view in cross section on the line 33 of Fig. 2. Fig. 4- is a plan view illustrating the action of the bending dies on a piece of stock.

Referring to the drawings, 2 indicates a frame or table upon which the various instrumentalities of the machine are mounted and upon which the stock to be operated upon is placed. The table 2 is provided at its edges with a downwardly extending web, for purposes of stiffening and strengthening it, and is supported at a convenient height from the ground by legs l. A. heavy boss 6 projects downwardly from the table and is provided with abushed bearing for the shank of a stationary forming die 8.

Extending longitudinally of the table, and preferably cast integral therewith, are parallel ribs 10 which form a part of a guideway in which is mounted for reciprocation a carrier 12 for the movable forming die 14:. The upper part of the guideway is formed by a cover plate 16 bolted to the ribs 10 and having upwardly extending ears or flanges 1.8 to one of which is pivotally connected a retaining bar 20 for the stationary die 8. The bar 20 is apertured at its outer end and adapted to fit over a stud projecting from the upper end of the stationary die 8, whereby the die is supported at its upper end against the thrust of the movable die 14. At the same time the die is left free on its rear side so that there is nothing to interfere with the movement of bent stock past the rear of the die and in close proximity thereto as would occur in shaping a narrow die.

Journal bearings are provided at the rear of the table 2 for the main shaft 22 which has on one end a heavy driving pulley 2 1 and at the ot er a bra e disk 26. Interposed between the pulley 24:, which, by reason of its weight also acts as a fly wheel, and the driving shaft 22 is a clutch of suitable construction by which the pulley 24 may be engaged or disengaged at willfrom the shaft 22. Preferably the clutch is of the Horton type and includes a rotatable disk 34: having a tooth or projection which may be engaged by an abutment 36 when it is desired to stop the machine, the withdrawal of the abutment from the path of the tooth permitting a rotary movement of the disk 34:, as is usual in this type of clutch, which effects engagement of the pulley and shaft. The abutment is provided with the usual cushioning spring and is mounted on one end of a transversely extending rock shaft 82. The rock shaft at its other end is connected to a bell crank lever 30 which carries a brake shoe 28 adjacent to the disk 26 and is normally moved by a spring 31 to force the brake shoe against the disk 26 and to keep the abutment 36 in the path of the projection on the clutch disk 34:. The rock shaft 32 may be turned to release the brake and permit the-clutch to engage by depressing a treadle rod 38 which turns the rock shaft through an arm 40 against the action of the spring 31. The brake disk 26 is provided with an eccentric portion which, at a predetermined point in the rotation of the disk, engages the brake shoe 28, when the latter is not retracted by the treadle, and insures stopping of the machine with its parts in their initial position.

Reciprocatory movement of the die 1+1 toward and from the stationary die 8 is effected, in the embodiment of the invention herein illustrated, by means of an eccentric 4-2 formed integral with, or otherwise rigidly secured to, the shaft 22 and acting on the carrier 12 through an eccentric rod a l. The eccentric rod is pivotally connected to the rear end of a sliding head 46, which, in turn, is connected with the carrier 12 by a right and left screw lS. Each revolution of the driving shaft 22, therefore, imparts a complete reciprocation to the movable die 1% and a piece of stock held between the dies will be bent in accordance with the shape of the dies employed and their relative position at the point of nearest approach.

Preferably the stationary die 8 will be the male die and the movable die 14 will be the female die so that the stock will be bent curately to the desired contour it has been found advantageous to effect the bending as a progressive operation, that is to increase the curvature gradually until the desired contour is obtained. This result may be accomplished by causing the two forming dies to approach each other more closely at each successive relative movement, or after each few relative movements. In the machine herein described, manually controlled means are provided by which the reciprocatory die may be moved independently of its reciprocatory movement so that it will be carried closer and closer to the stationary die, although the same result could be obtained by progressively moving the stationary die toward the reciprocating die.

As shown in the drawings, the right and left screw 48 has elongated gear teeth formed thereon and meshing with said gear teeth is a hand wheel 50 having gear teeth on a part of its periphery. The hand wheel is rigidly connected to a horizontal spindle 52 having bearings in the ears or flanges 18. By turning the hand wheel 50 in the proper direction the die carrier 12 is moved nearer to the stationary die and the point of nearest approach of the two dies is thereby varied. In other words, the path of reciprocation of the die 14 is shifted with respect to the stationary die.

In order to prevent the pressure of the stock against the die 14 and the carrier 12 from turning the screw 48 reversely it has been found desirable to provide means for opposing turning of the screw 48 during the forward stroke of the carrier. One method of effecting this result is shown in Fig. 2 in;

which 54 indicates a hardened sector loosely supported by the spindle 52 and extending into proximity to the flange of the hand wheel 50. A pin 56 projecting from the rear flange 18 through an aperture in said sector prevents it from turning about the spindle 52. Set in the base of the forward flange 18, on the opposite side of the flange of the hand wheel 50 from the sector 54, is a hardened friction piece 58. Means, acting on the forward movement of the carrier, are provided for forcing the sector 54 against the hand wheel 50 and clamping its flange between the sector and the friction piece 58, thus preventing turning of the screw 48. To this end a sliding bar 60 is mounted in the cover plate 16 with its forward end bearing against the sector 56, and a lever 62 carrying a spring pressed Pin 64, bearing against an angular projection on the sliding bar 60, is arranged to force the bar 60 forwardly on the forward stroke of the reciprocatory die 14. The lower end of the lever 62 is received in a recess formed in the upper side of the head 46 into whichthe rear end of the right and left screw 48 is threaded. so that when the head 46 mow forwardly the lever62 is swung forwardly ing bar- 20, as already explained.

about its axis-and the spring pressed pin 64, accordingly, acts to press the bar 60 against the friction sector 54.

In order to limit the extent to which the movable die 14 may be advanced toward the stationary die by turning the right and left screw 48, a controlling device, comprising an arm 70, having an angularly disposed end, is rigidly connected with the rear end of the spindle 52 of the hand wheel and adjustable stops 72 are arranged in the path of the end of this arm. The arm will be turned with the hand wheel 50 and will, therefore, limit its angular movement by engaging one of the stops 72. The

stopmay be adjusted preliminarily in accordance with the thickness of the stock to be bent and breakage of the machine is thereby'avoided, it being obvious that this would occur if the die 14 were to be ad- I the stationary die 8 is' held by' its shank projecting downwardly into the boss 6 and the stud which is engaged by the retain- In operation, the stock to be bent is first heated and the retaining bar 20 is swung f up into the dotted line position shown in Fig. 2 permitting the stock to be placed on edgeon the plane surface of the table 2 "between the two forming dies. The bar 20 is then allowed to fall and engage the stud of the stationary die, The machine is set inoperation by depressing the treadle rod 38 whereupon'the die 14 is moved toward the stationary die, engaging the stock as indicated in the full line position in Fig. 4

and slightly bending it about the stationary male die 8. The die 14 is then retracted and during this movement the operator may change the position of the stock if 'necessary or may turn the hand wheel to'advance the die and its carrier so that at its next forward movement it will approach nearer to the die 8, for example, into the dotted line position shown in Fig. 4, bending the stock more sharply. The die 14 may be advanced closer to the die 8 at each reciprocation or after each two or three reciprocations, depending upon the skill of the workman and the behavior of the stock being operated upon. The operator then removes the bent stock and compares it with a. pattern or templet giving the contour desired, subjecting the stock to such further heating and bending as the case may require.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1, In a machine of the class described, the combination with a table having a surface to support the stock, a power driven female die arranged for reciprocation in a path above the supporting table, a stationary male die having its lower end extending for support below the surface of thetable, and a hinged retaining bar constructed and arranged to detachably engage and support the upper end of said male die leaving the rear side of the die free of obstruction to the movement of the bent stock about it.

2. A machine of the class described having, in combination, coiiperating dies, means for reciprocating one of said dies toward and from the other die, a screw op'eratively disposed with respect to one of said dies and arranged for shifting said die to adjust the point of nearest approach of the two dies, said screw being freely rotatable during the reverse stroke of the reciprocatory die and having means associated therewith for holding it against turning during the working stroke thereof.

3. A machine of the class described having, in combination, cooperating dies, means for reciprocating one of said dies toward and from the other die, a screw operatively disposed with respect to one of said dies for shifting the die-to adjust the point of nearest approach of the two dies, and means operating automatically for preventing turning of said screw during the working stroke of the reciprocating die.

4. A machine of the class described having, in combination, cooperating dies, means for reciprocating one of said dies toward 7 the other die, rotatable means including a hand wheel for adjusting the relative positions of the two dies and a controlling arm arranged to turn with the hand wheel for limiting the movement of said rotatable means.

5. A machine of the class described having, in combination, a stationary die, a reciprocatory die, a manually operated device for moving said reciprocatory die independently of its reciprocation, and controlling means movable with said device for limiting the extent of such independent movement.

6. A machine of the class described having, in combination, cooperating dies, means for reciprocating one of said dies toward and from the other die, a screw for shifting one of said dies to adjust the relative positions of the two dies, 2. hand wheel connected with said screw, and means acting to clamp said hand wheel during, the relative approach of the two dies.

7 A machine of the class described, having, in combination, cooperating dies, means for reciprocating one of said dies to and and from the other die, a screw for shifting one of said dies to regulate the relative positions of the two dies, a hand wheel acting on said screw for eii'ecting such regulation, and adjustable means for limitingthe turning movement of said hand wheel.

8. A machine of the class described having, in combination, a stationary die, a cooerating reciprocatory die, a carrier therefor, a screw for adjustably connecting the die and the carrier, and means for preventing said screw from turning in said carrier when the carrier moves in one direction, said means being arranged to act automatically regardless of the adjusted position of the die.

9. A machine of the class described having, in combination, co perating dies, mechanism including a hand wheel for regulating the relative position of said dies, means for moving one of said dies toward the other die, and means for holdingsaid hand wheel against turning during such movement.

10. A machine of the class described having, in combination, cotiperating dies, mechanism including a hand wheel and screw for regulating the relative position of said dies, a movable clamping member disposed adj acent to said hand wheel, a head movable toward and from one of said dies, and a die carrier for the other die movable with said head, a sliding bar arranged to move said clamping member into engagement with said hand wheel and an actuating lever for said. sliding bar movable about its during the working stroke of the movable die to effect the clamping of the hand wheel.

11. A machine of the class described having, in combination, a supporting frame, a shaft journaled therein, stationary and reciprocating dies mounted thereon, an eccentric on said shaft, and interposed connecting mechanism between said shaft and reciproeating die including a right and left screw, a manually operated device for turning said screw, and means for preventing turning said device during the working stroke of said reciprocating die arranged to release the device during the reverse movement of the die.

12. A machine of the class described having, in combination, a stationary die, a reciprocatory die, manually operated means for moving said reciprocatory die independently of its reciprocation, controlling means for limiting the extent of such independent movement, and a device for regulating the time when such movement may occur.

l3. Amachine of the class described hav- -when such regulating movement may occur.

let. A machine of the class described having, in combination, a supporting frame, a stationary die mounted thereon, a cooperating movable die, means for reciprocating said movable die continuously, and meanscapable of operation only while the die is moving reversely to cause said die to approach the stationary die more closely at successive reciprocations.

15. In a machine of the class described, the combination, with a frame having a surface to support the stock to be bent, a power driven die, a cooperating stationary die supported at its lower end beneath the surface of the table and unobstructed at its rear side, a retaining bar detachably connected to the upperend of said stationary die and extending in ,a direction parallel to the path of the power driven die, and a hinged connection between the frame and retaining bar permitting the bar to be disengaged from the stationary die for the presentation of stock thereto.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HARRISON H. EATON.

Witnesses:

CHESTER E. ROGERS, LAURA M. Goomunen.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. 0.

It is hereby certified that in Letters Patent No. 1,170,227, granted February 1,

1916, upon the application of Harrison H. Eaton, of Beverly, Massachusetts, for an improvement in Metal-Bending Machines, errors appear in the printed specification requiring correction as follows: Page 1, line 94, afterthe Word rotate.

insert the Word reversely; page 4, line 117, claim 11, after the Word turning insert the Word of; and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the ease in the Patent Office.

Signed and sealed this 25th day of April, A. D., 1916 [sEAL.] J. T. NEWTON,

Cl. 153-21. Acting Commissioner of Patents. 

